Typically, impact absorption materials are fixed directly to interior materials of vehicles. For example, a known impact absorption material has a lug that is fixed to a steel plate of a vehicle body with screws. Another known impact absorption material has a thin-plate flange. The flange projects from the outer periphery of the impact absorption material and is fixed to the vehicle body with fixing members. Furthermore, another known impact absorption material is fixed directly to an interior material with an adhesive agent. Under normal conditions (under conditions other than side collision), however, the fixed portions of the impact absorption materials can be damaged by long-term continuing shaking. This can result in falling of the impact absorption materials.
In order to avoid this, a conceivable replacement of such direct fixation of the impact absorption material to the interior material is fixation via a holder provided separately from the impact absorption material. In this case, the impact absorption material will be placed between the holder and the interior material; and then, the holder will be fixed directly to the interior material. The holder will have, for example, an accommodating body having a concavity, and a lug to fix the accommodating body to the interior material. With this structure, the impact absorption material can be accommodated in the accommodating body, while the lug can be fixed to the interior material. This can prevent the impact absorption material from falling.
However, the accommodating body will have a frame that surrounds a peripheral surface of the impact absorption material. The frame tends to withstand an impact while transferring the impact onto the interior material. This results in a higher load on the occupant in the event of side collision. Namely, in order that the load on the occupant is less, the holder needs to have a lower strength. Thus, to provide the lower strength of the holder in the event of side collision and to prevent the impact absorption material from falling under the normal conditions are mutually contradictory problems, and solving both problems together is difficult.
Thus, there is a need for a structure that makes it possible to overcome these contradictory problems together.